【明報專訊】How do you tell a seal and a sea lion apart? There is a very simple way — sea lions have ear flaps, while seals don't. There are other noticeable differences too. For example, on land seals tend to wiggle about on their bellies using their small front flippers (腳蹼), while sea lions "walk" on their large flippers. Today we are looking at a special species of seals called spotted seals (斑海豹), which are found mostly in the inshore regions of the North Pacific and the Arctic Ocean.

Unspotted days

Spotted seals are not born with their spots. In fact, the pups are born with a dense, white coat called lanugo (初生毛), which makes them extremely cute and fluffy-looking. The pup loses its lanugo about a month after birth, when it begins weaning: that is, it stops taking milk from its mom. A smooth, grey-white coat with dark spots begins to cover the growing pup and gives it its unmistakable look, all the way into adulthood.

Harsh life out there

At the same time a spotted seal gains its spots, it starts to leave the ice and learns to forage in the sea. Nursing time with mom is now officially over and the pup is left to fend for itself! Life is harsh in the polar waters. Only about half of the spotted seal pups survive their first year.

Into adulthood

A full-grown spotted seal can be 1.7 metres long and its streamlined (流線型的), blubber-padded body can weigh between 65 and 115 kg. Males are considerably larger than females. Their hind flippers (後腳蹼) face backwards and cannot be turned toward the front like those of sea lions. This is why spotted seals move around on land in a funny wiggling motion with their front flippers. Spotted seals also have a very keen sense of smell, and can dive to a depth of 300 metres.

Favourite hang-outs

Spotted seals like "hauling-out", during which they gather on the shore or sea-ice in numbers that can reach over 10,000! In late spring and early summer, spotted seals leave the sea-ice and haul out on beaches or sandbars when they are not foraging in the waters. As winter approaches and the sea-ice forms, they once again return to their favourite icy spots.

Act now on climate change

Like many other species, spotted seals are under threat from climate change, which causes the reduction of and instability in sea ice. Climate change is being hastened by the massive release of greenhouse gases. Reducing energy consumption is something that can be done by everybody! For example, we can unplug electronic devices like computers when they are not in use. Instead of air-conditioners, we can use fans to cool ourselves.

Text and photos: Ocean Park Hong Kong

■Glossary

wiggle (v) 搖動

harsh (adj) 艱苦的

forage (v) 搜尋食物

massive (adj) 大量的

[Smarties' Power English 第232期]